|Minimum test pressure
|Minimum shell thickness
||5 mm for tanks up to 1.80 m diameter and for larger tanks carrying solids of packing group II or III; 6 mm otherwise.
|Bottom opening provisions
||2 shut-off devices required.
||T2, T3, T4, T5, T6, T7, T8, T9, T10, T11, T12, T13, T14, T15, T16, T17, T18, T19, T20, T21, T22
Special packing provisions:
- The degree of filling prescribed in 18.104.22.168.2 shall not be exceeded.
- The maximum degree of filling (in %) for solids transported above their melting points and for elevated temperature liquids shall be determined in accordance with 22.214.171.124.5.
- A substance under this description shall only be transported in a portable tank under an approval granted by the competent authority.
- Only inorganic non-combustible materials shall be used for thermal insulation of the tank.
- When transported under heated conditions, the heating device shall be fitted outside the shell. For UN 3176, this provision only applies when the substance reacts dangerously with water.
For UN Nos. 0331, 0332 and 3375, portable tanks may be used subject to the following conditions:
- To avoid unnecessary confinement, each portable tank constructed of metal shall be fitted with a pressure relief device that may be of the re-closing spring-loaded type, a frangible disc or a fusible element. The set-to-discharge or burst pressure, as applicable, shall not be greater than 2.65 bar for portable tanks with minimum test pressures greater than 4 bar.
- For UN 3375 only, suitability for transport in tanks shall be demonstrated. One method to evaluate this suitability is test 8 (d) in Test Series 8 (see Manual of Tests and Criteria, part 1, subsection 18.7).
- Substances shall not be allowed to remain in the portable tank for any period that could result in caking. Appropriate measures shall be taken to avoid accumulation and packing of substances in the tank (e.g. cleaning, etc).
- The portable tank instruction assigned for this substance applies for granular and powdered solids and for solids which are filled and discharged at temperatures above their melting point and which are cooled and transported as a solid mass. For solids which are transported above their melting point, see 126.96.36.199.
- Fusible elements in the vapour space may be used on portable tanks.
- The 2.5 year internal examination may be waived or substituted by other test methods or inspection procedures specified by the competent authority or its authorized body, provided that the portable tank is dedicated to the transport of the organometallic substances to which this tank special provision is assigned. However this examination is required when the conditions of 188.8.131.52.7 are met.